Amino-phosphorylchloride hardeners



United States Patent No Drawing. Filed July 25, 1962, Ser. No. 212,465 7 Claims. (Cl. 96-111) This invention relates to light sensitive gelatino silver halide emulsions containing amino-phosphorylhalide hardeners.

Various gelatin hardeners are known for light sensitive emulsions but some of the compounds considered previously for that purpose have exhibited certain disadvantageous auxiliary characteristics which have decreased their usefulness for this purpose.

One object of my invention is to provide a hardener for gelatino silver halide photographic emulsion layers in which the photosensitive properties of the silver halides therein are not adversely affected. Other objects of my invention will appear herein.

I have found that certain amino-phosphorylhalide compounds are useful as hardeners for gelatin when incorporated in gelatino silver halide emulsions, preferably in a proportion 0.36% of the gelatin. I have found that incorporation of these compounds increases the resistance of the emulsion layer to hot water while at the same time having a low effect on contrast and some anti-fogging action. Gelatino-silver halide emulsions are characterized by the presence of gelatin in the protective colloid for the silver halide therein.

The compounds which have been found to be useful as gelatin hardeners have a formula (I) R NPOX (II) (R N) POX in which R is lower alkyl, e.g. methyl or ethyl and X is a halogen, particularly a chlorine, fluorine or bromine atom. The emulsion layer containing the hardener after coating out onto a support and drying for 18 hours at 15 C. has melting points of the order of at least 100 F. The hardeners in accordance with my invention may be employed in gelatin-silver halide photographic emulsions to give layers or coatings which upon drying exhibit good resistance to water or aqueous conditions at elevated temperature.

The hardening agents used in accordance with my invention are desirably employed in the proportion of 0.3-6 parts per 100 parts of gelatin. My invention relates to increasing the resistance of gelatin-silver halide photographic emulsions to elevated temperatures. The compounds used as hardeners may be either dialkylaminophosphoryldihalides, or bisdialkylaminophosphorylhalides; As the gelatin ordinarily for photographic purposes must have high jelly strength that is of a bloom value of at least 250 grams, my invention is particularly useful in hardening layers of photosensitive emulsions in which high jelly strength gelatin is employed as the carrier for silver halide.

The following examples illustrate my invention:

Example 1 Samples of a fine-grain negative type sensitive gelatinsilver bromoiodide emulsion containing 67% of gelatin had incoporated therein different proportions of dimethylaminophosphoryldichloride and bisdimethylaminophosphorylchloride. The emulsion sample without hardener and the samples having therein the compounds referred to were each coated onto a cellulose triacetate film support and were subjected to various tests (a) 1 week after coating and (b) one week after holding at 42% RH. and

3,125,449 Patented Mar. 17, 1964 "ice F. such as for speed, fog, contrast, and melting point, the latter determined when the emulsion is immersed in water and the temperature is increased from room temperature up to the boiling point of the water. The results obtained with the chlorides were as follows:

1 week after coating 1 week at 42% R.H. and 120 F.

Control 4. 30 24 89 94 Control Compound (I; R=Me) 0.3 g./l.) 4. 32 21 86 103 Control Compound (I; R=Me) (1.0 g. l 4. 24 16 87 180 Control Compound (II; R=Me) (0.3 g./ 4. 33 19 85 Control Compound (II; R=Me) The product, after it had been coated for 3 months, was run through the same series of tests and the following results were obtained:

Samples of the film after standing for 6 months were run through this series of tests and the following results were obtained:

6 months after coating Rel. Fog Con- M.P. Speed trast F.)

Control 4. 30 0. l9 0. 94 92 Control Compound (I; R=Me) (1.0 g./l.) 4.21 0.13 0.88 198 Control Compound (II; R=Me) Example 2 The above example was repeated except that the corresponding fluoride compounds (dimethylaminophosphoryldifluoride and bisdimethylphosphorylfluoride) were employed in place of the chlorides used in Example 1, the quantities being unchanged. The fluorides gave characteristics substantially equivalent to those imparted by the chlorides in the photographic emulsions of Example 1.

Example 3 Hardeners were used having the following formulas:

(IV) Et NPOCI (V) (Et N) POCl and (VI) (Et N) POF These hardeners were incorporated in a gelatin-silver halide photographic emulsion and coated out in the form of layers thereon. Tests were run on the layers as indicated in the following tables and the results which were obtained were those given comparing the speed, fog, contrast, and melting points of the different layers:

1 week after coating Rel. Fog Con- M.1

Speed trast F) Control 4. 37 .20 98 91 Control Compound (IV) (1.0 g 4. 31 .16 .98 95 Control Compound (IV)(3.0 g 4. 21 12 .98 100 Control Compound (V) (1.0 g. 4. 32 .17 1. 96

1 week at 42% RH. and 120 F.

Compound (VI) bi'sdiethylaminophosphorylfluoride as a hardener acted similarly to the corresponding chloride in the gelatin-silver halide emulsion.

I claim:

1. A light sensitive gelatin-silver halide photographic emulsion containing a hardener selected from the group consisting of R NPOX and (R N) POX, R being lower alkyl and X being halide.

2. A light sensitive gelatin-silver halide photographic emulsion containing as a hardener therein R NPOCI R being lower alkyl.

3. A light sensitive gelatin-silver halide photographic emulsion containing as a hardener therein (R N) POCl, R being lower alkyl.

4. A light sensitive gelatin-silver halide photographic emulsion containing as a hardener therein (R N) POF, R being lower alkyl.

5. A light sensitive gelatin-silver halide photographic emulsion containing as a hardener therein Et NPOCI Et representing ethyl.

6. A light sensitive gelatin-silver halide photographic emulsion containing as a hardener therein (Et N) POCl, Et representing ethyl.

7. A light sensitive gelatin-silver halide photographic emulsion containing as a hardener therein (Et N) POF. Et representing ethyl.

No references cited. 

1. A LIGHT SENSITIVE GELATIN-SILVER HALIDE PHOTOGRAPHIC EMULSION CONTAINING A HARDER SELECTED FROM THE GROUP CONSISTING OF R2NPOX2 AND (R2N)2POX, R BEING LOWER ALKYL AND X BEING HALIDE. 